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    <title>coff</title>
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    <center>Scilab Function</center>
    <div align="right">Last update : April 1993</div>
    <p>
      <b>coff</b> -  resolvent (cofactor method)  </p>
    <h3>
      <font color="blue">Calling Sequence</font>
    </h3>
    <dl>
      <dd>
        <tt>[N,d]=coff(M [,var])   </tt>
      </dd>
    </dl>
    <h3>
      <font color="blue">Parameters</font>
    </h3>
    <ul>
      <li>
        <tt>
          <b>M</b>
        </tt>: square real matrix</li>
      <li>
        <tt>
          <b>var</b>
        </tt>: character string</li>
      <li>
        <tt>
          <b>N</b>
        </tt>: polynomial matrix (same size as <tt>
          <b>M</b>
        </tt>)</li>
      <li>
        <tt>
          <b>d</b>
        </tt>: polynomial (characteristic polynomial <tt>
          <b>poly(A,'s')</b>
        </tt>)</li>
    </ul>
    <h3>
      <font color="blue">Description</font>
    </h3>
    <p>
      <tt>
        <b>coff</b>
      </tt> computes R=<tt>
        <b>(s*eye()-M)^-1</b>
      </tt> for <tt>
        <b>M</b>
      </tt> a real matrix. 
    R is given by <tt>
        <b>N/d</b>
      </tt>.</p>
    <p>
      <tt>
        <b>N</b>
      </tt> = numerator polynomial matrix.</p>
    <p>
      <tt>
        <b>d</b>
      </tt> = common denominator.</p>
    <p>
      <tt>
        <b>var</b>
      </tt> character string ('<tt>
        <b>s</b>
      </tt>' if omitted)</p>
    <h3>
      <font color="blue">Examples</font>
    </h3>
    <pre>

M=[1,2;0,3];
[N,d]=coff(M)
N/d
inv(%s*eye()-M)
 
  </pre>
    <h3>
      <font color="blue">See Also</font>
    </h3>
    <p>
      <a href="../polynomials/coffg.htm">
        <tt>
          <b>coffg</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="../control/ss2tf.htm">
        <tt>
          <b>ss2tf</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="nlev.htm">
        <tt>
          <b>nlev</b>
        </tt>
      </a>,&nbsp;&nbsp;<a href="../programming/poly.htm">
        <tt>
          <b>poly</b>
        </tt>
      </a>,&nbsp;&nbsp;</p>
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